Jeremy Corbyn has called on Prime Minister Theresa May to protest Saudi Arabia’s war in Yemen during the visit of the kingdom’s crown prince to London.

The British opposition Labour Party leader said Tuesday that May should tell Crown Prince Mohammed bin Salman that Britain would stop providing arms to Riyadh.

Bin Salman’s three-day visit will begin with a lunch with Queen Elizabeth on Wednesday.

His stay in the UK will include two audiences with the British Royal family, a briefing with national security officials, and a visit to the prime minister’s country residence.

“Theresa May should use this visit to announce the UK will no longer supply arms to Saudi Arabia while the devastating Saudi-led bombing of Yemen continues and make clear Britain’s strong opposition to widespread human and civil rights abuses in Saudi Arabia,” Corbyn said.

Saudi Arabia and its partners launched a war on Yemen in March 2015 to reinstall its former Riyadh-allied government. The military aggression has so far killed over 13,600 Yemenis.

The war is being led by bin Salman, also Saudi Arabia’s defense minister, with the help of the US and the UK.

May’s government has remained defiant in the face of growing pressure to stop arms exports to Saudi Arabia, defending the sales amid evidence of war crimes and civilian deaths in Yemen.

The UK has increased its weapons sales by around 500 percent since the onset of the Saudi invasion, according to a report by The Independent.

The UK has, so far, sold more than six billion pounds of arms to Saudi Arabia.

The weapons sold by Britain, which has also been providing logistical and arms support for the bombardment, include precision-guided bombs.